Why is the 3D print so bad with cracks. uses ABS+ filament

ABS shrinks as it cools down… the taller the print, the more likely to delaminate.

In order to avoid it, heat bed to 100º - 115º and get your printer in an enclosure for a stable temperature inside. This is not that easy as one may think, you would want to take all the electronics out.

If you have no enclosure, ABS is proner to shrink and delaminate as you have experienced.